Bug 2520812 (CVE-2026-77642)

Summary: CVE-2026-77642 tor: Tor: Denial of Service via out-of-bounds write in signature parsing
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in Tor. This out-of-bounds write vulnerability occurs when Tor parses a consensus or detached signature with an unexpected signature digest type. A remote attacker could exploit this to cause a denial of service for Tor directory authorities, potentially disrupting the Tor network. While the impact is minor for most Tor roles, it could be significant for directory authorities.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2521290, 2521291    
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Description OSIDB Bzimport 2026-08-20 21:48:56 UTC
tor before 0.4.9.9 was prone to anĀ out-of-bounds write when parsing a consensus or  detached signature with unexpected signature digest type. Impact  is minor for most Tor roles, but potentially major for directory   authorities. This is TROVE-2026-019.